中文摘要：

20世纪70年代后，随着社会、经济发展需要，美国开始进入养老金制度改革时期，并通过改革推动其多支柱的养老金计划进行了多项调整。美国的养老金制度改革并非强制性的颠覆式革新，而是根据人口年龄结构、经济发展对劳动力流动的需求，以及劳动力收入水平等外在环境的变化而进行的渐近式权变。经过近四十年的改革，美国养老金制度的基本结构己悄然发生改变，但仍呈现出较强的代内、代际收入再分配能力。这不仅有效保障了各收入阶层劳动者的晚年生活水平，而且使各代退休者的收入水平呈现稳中有升的趋势。其较为成功的改革模式，为人口基数大、转轨成本高的我国养老金制度的完善和发展提供了宝贵的实践经验。

英文摘要：

According to the development of social and economic, the pension system of United States entered the reform era since 1970s. During the time, the reform has promoted the occupational pension plan from the traditional treatment system to DC system, and has made some adjustment to other pillar of the pension plans. Nevertheless, it is not a subversive or mandatory innovation, but a kind of asymptotic development adapt to the change of population age structure and the change of labor mobility needs. In the past 40 years, the pension system of United States still has powerful ability of income redistribution whatever to intra-generation or inter-generation, and the reform not only guaranteed the elderly life for various income groups but also promoted the income of all generation of retirees in United States. So, the pension reform of United States will provide valuable practical experience to China with large population base or high cost in pension system transition.